Abstract
The Robinson equation was modified and applied to the viscosity data of clay suspensions to which the Einstein equation was not applicable. The modified Robinson equation is:
ηrel-1=k'S'V/(1-S'V) where ηrel is the relative viscosity, V the volume concentration of clay particles (cm3/cm3), S' a parameter for the ratio of the effective volume of clay particles to their actual volume and k' another parameter related to particle-particle interaction. The S' value increased from about 10 for spherical halloysite suspensions to allophane, kaolinite, montmorillonite and up to 1900 for fibrous imogolite suspensions. The k' value increased from about 1 for deflocculated suspensions to 20 for flocculated suspensions.
